Transom drive for inboard motorboats



TRANSOM DRIVE FOR INBOARD MOTORBOATS Filed Feb. 6, 1962 2 Sheets-Sheet 1 (loxw mwx w June 21, 1966 A. G. ACKERMAN TRANSOM DRIVE FOR INBOARD MOTORBOATS 2 Sheets-Sheet 2 Filed Feb. 6, 1962 FIG-.5

FIG-6 3,256,851 TRANSOM DRIVE FOR INBOARD MOTORBOATS Albert Giles Ackerman, 416 Donnybrook Road, Oakville, Ontario, Canada Filed Feb. 6, 1962, Ser. No. 171,422 2 Claims. (Cl. 115-35) This invention relates to a propulsion and steering mechanism for a boat with inboard engine,.more particula'rly to a transom drive unit therefor of the type wherein an outboard propeller drive is powered by an inboard engine.

While drive units of the general type disclosed are not new, the units heretofore known have all incorporated certain undesirable and objectionable features. The units previously known generally lacked great flexibility in the tilting and steering angles attainable, being hampered by the limitations of the universal joints used. The present invention permits complete freedom of titling and steering angles and yet is simpler in construction than prior devices.

This greater flexibility and simplicity is attainable by using a novel universal joint. This universal joint has been applied to the present transom drive in a novel manner as will be shown to achieve a drive'unit of maximum utility and inherently simple construction.

A further object is to provide convenient means to adjust the tilt pivotal angle of the drive unit from within the boat.

A further object is to provide convenient means to retract the drive unit completely above the bottom of a boat from within the boat.

A further object is to provide tilt pivotal restraint wherein water drag on the submerged operative parts of the drive unit will not cause undesirable pivotal movement but will yield to collision impacts without damage to the submerged operative parts.

A further object is to provide forward-neutral-reverse operation of the drive unit, and further to permit reverse operation to be initiated while the boat is making full speed forward.

A further object is to provide adaptable mounting means whereby the drive unit may be universally mounted on transoms of various angles of construction in both the vertical and horizontal planes.

A further object is to supply the machine elements of the drive unit with a continuous supply of cooled lubrieating oil.

A further object of the transom drive is to counterbalance the steering elfect of the driving torque whereby turning the boat to port or starboard is effected with equal steering effort on the steering controls.

A further object of the transom drive is to provide means whereby the universal joint thereof is coveredwithout restraint of the tilting action of the drive unit.

Still other objects, features and advantages of the present invention not specifically set forth hereinbefore are those inherent in or implied from the novel construction, combination and construction of parts as will become more fully apparent as the description proceeds.

In drawings which illustrate an embodiment of the invention:

FIGURE 1 is an elevation of an embodiment in section taken substantially upon a vertical plane passing through the center line of the drive unit showing structural details thereof.

FIGURE 2 is fragmentary portion of the elevation of FIGURE 1 showing the universal joint in a position rotated 90 from that in FIGURE 1.

FIGURE 3 is a section of the line 3-3 of FIGURE 1 showing details of construction of the oil circulation system.

United States Patent FIGURE 4 is a rear elevation of an embodiment partially in section of the line 4-4 of FIGURE 1 showing structural details thereof. 1

FIGURE ,5 is a section of the line 5-5 of FIGURE 1 showing the steering swivel arrangement and further de tails of construction.

- FIGURE 6 is a section of the line 66- of FIGURE 4 showing the mounting and reverse-locking arrangements and further details of construction.

Referring now specifically to the drawings it will be seen that the numeral 10 generally designates the drive unit of the present invention being secured to the transom 11 of a boat in spaced relation above the bottom 12 thereof. Said transom 11 having an opening 13 over which a generally rectangular transom frame 14 is secured by a plurality of screw threaded bolts 15. An opening of said transom frame 14 having a flanged edge 16 forming a partial spherical recess wherein is positioned a matching spherical prominence 17 of amounting bracket 18.

Said mounting bracket 18 having a horizontal tubular body and spherical prominence 17 integral therewith and a radial adapting flange 19 on the forward end thereof. Positioned interiorly of said tubular body of mounting bracket 18 a tubular extension 20 of marine transmission 21, said marine transmission 21 being secured to the adapting flange 19 of mounting bracket 18 by a plurality of screw threaded cap screws 22. The rear cover of 1 said marine transmission 21 being further adapted having a multiplicity of longitudinal screw threaded studs 23 spaced about the outer edge thereof. Said longitudinally positioned screw threaded studs 23 having thereon screw threaded mounting nuts 24. Said screw threaded mounting nuts 24 being of the form of an interiorly screw threaded tube having a closed end of spherical radius, said closed end of mounting nuts 24 hearing against depressions 25 of aforementioned transom frame 14 secured to the transom 11 of a boat for a purpose hereinafter described.

Marine transmission 21 being of conventional construction preferably of the planetary gear type whereby an engine 118 operably connected to rotatable input shaft 26 thereof provides controllable forward-neutral-reverse rotation of a horizontal drive shaft 27 thereof by a controllable control lever 28 thereon. Said rotatable horizontal drive shaft 27 being extended aft outboard of a boat and concentric within aforementioned tubular extension 20 of the housing of said marine transmission 21 Said tubular extension 20 being positioned interiorly of the tubular body of mounting bracket 18 whereby the rotational axis of horizontal drive shaft 27 therein coincides with the longitudinal axis of said mounting bracket 18.

Said tubular extension 20 of marine transmission 21 extending aft the length of the tubular body of aforementioned mounting bracket 18, the horizontal drive shaft 27 concentrically journalled therein having multiple splines 29 on the aft end thereof. Secured to the aft end of said horizontal drive shaft 27 a drive fork 30, being of the form of a horizontal cylinder having two spaced rearwardly extending arms on the aft end thereof, the interior cylindrical bore therein having matching multiple splines 31 adapted to the multiple splines of said horizontal drive shaft 27, and further secured thereto by screw threaded cap screw 32 axially therein. An outer cylindrical surface of drive fork 30 being adapted for support by ball bearing 33 mounted interiorly of the tubular extension 20 of marine transmission 21 and further adapted to sealingly bear against an oil seal 34 similarly mounted interiorly of said tubular extension 21. Aforementioned mounting bracket 18 having two horizontally spaced arms 35 extending rearwardly from the tubular body thereof, in the aft end of each horizontally spaced arm 35 a screw threaded hole, said screw threaded holes lying on a comrnon horizontal pivotal axis athwartship the boat passing through the longitudinal axis of the tubular body of mounting bracket 18.

Pivotally depending from the mounting bracket 18 is a pivot bracket 36, being of the form of a horizontal substantially rectangular plate 37, spaced below the longitudinal axis of the mounting bracket 18, with upstanding spaced structural arms 38 on the port and starboard sides thereof. Said upstanding structural arms 38 of said pivot bracket 36 having circular holes 39 in the upper ends thereof, said circular holes 39 lying on an horizontal pivotal axis athwartship the boat coinciding with aforementioned pivotal axis of mounting bracket 18. Said pivot bracket 36 being pivotally secured to said mounting bracket 18 by screw threaded shoulder bolts 40' pivotal within the circular holes 39 of pivot bracket 36 and secured within the screw threaded holes of mounting bracket 18, whereby pivot bracket 36 is restrained from all but pivotal motion about a horizontal pivotal axis athwartship the boat. Said rectangular plate 3 7 of pivot bracket 36 having therein a horizontal circular opening 41, the axis of said circular opening 4-1 being substantially vertical intersecting aforementioned horizontal pivotal axis of said pivot bracket 36 but displaced laterally along said horizontal pivotal axis of pivot bracket 36 from the point of intersection of the longitudinal axis of mounting bracket 18 and said horizontal pivotal axis of pivot bracket 36.

Said horizontal circular opening 41 of rectangular plate 37 of pivot bracket 36 having therein two vertically spaced annular grooves, positioned in said annular grooves a multiplicity of bearing balls 42 swivelly positioning a horizontal swivel disk 43 therein. Said horizontal swivel disk 43 having two adaptable vertically spaced annular grooves in the outer surface thereof engaging said hearing balls 42. Said pivot bracket 36, Ibearing balls 42 and swivel disk 43 being operably positioned by a horizontal retainer ring 44 having an adaptable ball groove on the upper inner edge thereof and secured to the bottom surface of the rectangular plate 37 of said pivot bracket 36 by a multiplicity of screw threaded cap screws 45- whereby said swivel disk 43 is restrained from all but horizontal swivel motion within said opening 41 of pivot bracket 36.

Depending from the bottom surface of aforementioned swivel disk 43 a tiller bar 46, a spacer 47 and vertical tubular housing 48 being commonly secured thereto by two vertical cap screws 49 therethrough into said vertical tubular housing 48. Said vertical tubular housing 48 extending vertically downwardly from the lower horizontal surface of said spacer 47 to a point below the bottom 12 of a boat. Said swivel disk 43 being further adapted having a cavity in the upper surface thereof wherein is positioned ball bearing 50, said ball bearing 50 being further positioned axially by retainer ring 51 secured to the upper surface of said swivel disk 43 by a plurality of screw threaded fasteners 52, wherein vertical drive shaft and fork 53, 54 is journaled interiorly of a contiguous cavity 55 interiorly of said swivel disk 43, tiller bar 46, spacer 47 and vertical tubular housing 48. Rotatable driven fork 54 being secured to ball bearing 50 by an integral radial shoulder thereof and screw threaded retainer nut 56 thereon. Rotatable driven fork 54 being further adapted with a vertical cylindrical portion thereof sealingly contacting an oil seal 57 positioned interiorly of aforementioned retainer ring 51 secured to swivel disk 43. The axis of rotation of said vertical drive shaft and fork 53, 54 being substantially vertical and intersecting the point of intersection of the rotational axis of aforementioned horizontal drive shaft 27 and horizontal pivotal axis of aforementioned pivot bracket 36.

Vertical drive shaft and fork 53, 54 are integrally formed having a vertical drive shaft 53, with a driven fork 54 at the upper end thereof. Said driven fork 54 having, at the upper end thereof, two horizontally spaced vertically I upstanding arms for a purpose hereinafter to be described.

Said vertical drive shaft 53 having at the lower end thereof male multiple splines drivingly engaging conforming female multiple splines of bevel pinion and shaft 58. Said bevel pinion and shaft 58 being journaled within cavity 55 of tubular housing 48 by ball bearing 59 and roller bearing 60 whereby the bevel pinion of said bevel pinion and shaft 58 is positioned vertically interiorly of an enlarged horizontal bore 61 of the lower end of said cavity 55.

Journaled interiorly of said horizontal bore 61 of tubular housing 48 a propeller shaft 62 therein. The forward end of propeller shaft 62 being rotatably positioned by ball bearing 63 positioned in a depression of tubular housing 48 and the aft end thereof being journaled in ball bearing 64 positoned in horizontal bore 61 of tubular housing 48. Said propeller shaft 62 being axially positioned interiorly of horizontal bore 61 of tubular housing 48 by an enlarged cylindrical portion thereof spaced between aforementioned ball bearing 64 and a bevel gear 65 positioned on the forward end of said propeller shaft 62. Bevel gear 65 depending against aforementioned ball bearing 63. Bevel gear 65 being rotatable with said propeller shaft 62 through key 66 mutually therein, and in meshing engagement with the pinion of aforementioned bevel pinion and shaft 58. Ball bearing 64 being further positioned interiorly of horizontal bore 61 of tubular housing 48 by retainer ring 67, said retainer ring 67 being secured to said tubular housing 48 by matching screw threads on the outer surface thereof. Said retainer ring 67 being further adapted having oil seal 68 therein sealingly bearing upon propeller shaft 62.

On the after end of propeller shaft 62 is positioned propeller .69, being secured thereon by a shear pin 70 through matching transverse holes in said propeller shaft 62 and propeller 69, and screw threaded lock nut 71 of conical form with a cavity in the forward end thereof overlapping the ends of said shear pin 70. Said lock nut 71 being screw threaded to propeller shaft 62 and a transverse cotter pin 72 extending through screw threaded lock nut 71 and propeller shaft 62.

Tubular housing 48 being formed whereby an anticavitation plate 73 with integral rudder is positioned above said propeller 69, and positioned forwardly of propeller 69 and extending downwardly beyond the lower end thereof, a sloping protective projecting member 74 substantially in the nature of a skeg.

Aforementioned vertical drive shaft and fork 53, 54 journaled interiorly of cavity 55 .of tubular housing 48 being further adapted wherein a vertical divergent tube 75, divergent upwards, is concentrically positioned therearound. Said vertical divergent tube '75 being secured concentrically to vertical drive shaft 53 by an integral notched ring 76 thereof and screw threaded set screw 77 therein. The upper end of said vertical divergent tube 75 being positioned about the outer perimeter of retainer nut 56 positioned on driven fork 54. The cavity 55 of tubular housing 48 being additionally connected to the horizontal bore 61 at the lower end of said cavity 55 by vertical passage 78 interiorly of tubular housing 48 for a purpose hereinafter to be described.

Aforementioned drive fork 30 positioned on the end of rotatable horizontal drive shaft 27 of marine transmission 21 has a pivot pin 79 pivotally positioned through the rearwardly extending spaced arms thereof. Said pivot pin 79 has a pivotal axis perpendicular to and intersecting the rotational axis of said horizontal drive shaft 27 and drive fork 30. Said pivot pin 79 is secured within a bore through link block 80 by screw threaded set screw 81 whereby said link block 80 is pivotally positioned between said spaced arms of aforementioned drive fork 30. Said link block 80 having two parallel spaced bores perpendicular to the bore of pivot pin 80, said parallel bores being equally spaced either side of the rotational axis of said drive fork 30 Link pins 82 being positioned interiorly of said parallel spaced bores of link block 80, and axially restrained in link block 80 by clearing notches thereof engaging said pivot pin 79 secured in said link block 80, whereby the ends thereof protrude beyond the edges of said link block 80. Pivotally positioned on the protruding ends of each link pin 82 is the forked end of a drive link 83 whereby said link block 80 is positioned between spaced arms of drive links 83. Drive link 83 being' substantially Y shaped having parallel spaced bores through the forked and plain ends thereof. The parallel bore of the plain end of drive link 83 being pivotally connected to a like parallel bore of a like driven link 83 by link bolt 84 and link nut 85, whereby pivotal motion between like drive link 83 and driven link 83, in a plane, perpendicular to the pivotal axis of link pin 82 therethrough and containing the pivotal axis of pivot pin 79 of link block 80, is freely made. Said driven links 83 being identical to drive links 83 but being oppositely positioned with respect to said plane perpendicular to the longitudinal axis of link pin 82. The forked ends of driven links 83 being identically pivotally secured to a horizontally positioned identical link block 80 by identical link pins 82 in spaced parallel bores of said link block 80. Said horizontally positioned link block 80 being pivotally secured by an identical pivot pin 79, secured therein by screw threaded set screw 81, between aforementioned upstanding horizontally spaced arms of driven fork 83.

The aforementioned upstanding spaced structural arms 38 of pivot bracket 36, pivotally depending from mounting bracket 18, being adapted in the form of a sheave segment 86 with radius axis on the horizontal pivotal axis of said pivot bracket 36. The edge of said sheave segment 86 having a groove wherein is positioned a flexible tension cable 87, said flexible tension cable 87 passing from one sheave segment 86 to the other sheave segment 86 across the front edge of rectangular plate 37 of pivot bracket 36, and being clamped therein by clamp 88 and screw threaded cap screws 89 therein. The free ends of said cable 87 passing tangentially forward from the top of said sheave segment 86 through the openings 90 in the transom 11 of a boat and through tubular stop brackets 91 secured to the inside of said transom 11 by a plurality of screw threaded wood screws 92. Said tubular stop bracket 91 being screw threaded on the outer cylindrical surface thereof whereon a tubular stop 93, having matching screw threads on the inner bore thereof, may be longitudinally telescopically positioned. Said free ends of cable 87 passing forward through said tubular stop bracket 91 and tubular stop 93 whereat said cable 87 is secured by conventional means into cable terminations 94. Said cable termination 94 being larger than the opening of tubular stop 93 and having a suitable loop thereon for securing thereto a flexible tension member 95 for a purpose hereinafter to be described.

Aforementioned tiller bar 46 secured to swivel disk 43 being of the form of a horizontal bar with upstanding horizontally spaced arms on the outer ends thereof. Said upstanding spaced arms of said tiller bar 46 having in the upper ends thereof a vertical bore 96, a cylindrical swivel 97 swivelly positioned therein by screw threaded set screw 98 of tiller bar 46 engaging an annular groove of said swivel 97. The upper end of said swivel 97 being vertically slotted whereby the looped end of tiller cable 99 is swivelly positioned in said slot by a horizontal pin 100 therethrough. Said tiller cables 99 passing forward through openings 101 in the transom 11 of a boat, said openings 101 in the transom 11 and aforementioned horizontal pins 100 lying in a horizontal plane through the rotational axis of horizontal drive shaft 27 of marine transmission 21 for a purpose hereinafter 'to be described.

Aforementioned marine transmission 21 being further adapted whereby a lug 102 and post 103 are positioned below and behind control lever 28 thereof. Depending from said post 103 a tension spring 104, said tension 'spring 104 tending to position the forward end of reverse lock lever 105 below the lower end of said control lever 28 of marine transmission 21 against lug 102 thereof. The forward end of said reverse lock lever 105 being of clearing arcuate form with radius center on the pivotal center of controllable control lever 28 of marine transmission 21. Said reverse lock lever 105 passing aft, through opening 13 of the transom 11 of a boat, through an opening 106 of the transom frame 14 secured to said transom 11, and pivotally secured to mounting bracket 18 by a screw threaded shoulder bolt 107. The outboard end of said reverse lock lever 105 being formed with an integral hook 108 thereon and inclined engaging face whereby said reverse lock lever 105 lockingly engages a horizontal shear pin 109 secured to a structural arm 38 of pivot bracket 36 pivotally depending from mounting bracket 18 for a purpose hereinafter to be described.

Side covers 110 are secured to aforementioned transom frame 14 and aforementioned shoulder bolts 40 by a multiplicity of screw threaded screw fasteners 111 therein. Said side covers 110 being vertical flat panels conforming to the transom 11 and having horizontal parallel upper and lower edges joined by an are on the rear edge thereof, said are having radius centre on the pivotal axis of aforementioned pivot bracket 36. Said side covers 110 having an inwardly extending flange 112 on the top, bottom and rear edges thereof. Said flange 112 being spaced radially clearingly beyond the edge of sheave segment 86 integral with structural arms 38 of pivot bracket 36. Freely positioned between said side covers 110 and further positioned between the flanges 112 thereof and cable 87 of the sheave segments 86 of pivot bracket 36 are multiple spaced horizontal rods 113. Said horizontal rods 113 being mutually conjoined in hinging fashion by a multiplicity of accordian panels 114 clearingly between the inner edges of the flanges 112 of side panels 110. Said accordian panels 114 having two half-panels hingingly connected by horizontal hinge rods 115. The ends of horizontal rod 113 nearest transom 11 of a boat being secured to side covers 110 by means not shown in the drawings. Said multiplicity of accordian panels 114 positioned by restrained, connecting, horizontal .rods 113 forming an upper and rear surface between spaced side covers 110. The last accordian panel 114 overlappingly covering an arcuate extension 116 of the rear upper edge of rectangular plate 37 of pivot bracket 36, the last halfpanel thereof being secured to said pivot bracket 36 by tension spring 117 for a purpose hereinafter to be described.

In operation power is supplied to the input shaft 26 of marine transmission 21 by a suitable engine 118. The rotation of horizontal drive shaft 27 of marine transmission 21 and drive fork 30 thereon being controllably e f-- 83 pivotally depending therefrom. Said drive links 83- transmitting torque to like driven links 83 pivotally connected thereto by link bolt 84 and link nut 85. Said driven links 83 further transmitting torque to link block 80 pivotal thereon, through link block 30 to pivot pin 79 therein. Said pivot pin 79 being pivotally positioned in rotatable vertical driven fork 54 whereby torque is transmitted thereto. transfer torque from drive fork 30 to driven fork 54, further maintaining the pivotal axis of pivot pin 79 of horizontal drive fork 30 and the pivotal axis of pivot pin 79 of vertical driven fork 54 in a common rotatable plane at all rotatable positions thereof. It may further be seen that due to the pivotal relationship of the above several parts the rotatable vertical driven fork 54 journaled interiorly of swivel disk 43 can receive continuous torque As described the above several parts from horizontal drive fork at all pivotal angles of pivot bracket 36 and swivel disk 43 swivelly therein. It may still further be seen that said rotatable vertical driven fork 54 journaled interiorly of swivel disk 43 can receive continuous torque from horizontal drive fork 30 at all horizontal displacements thereof resulting from swivel movement of swivel disk 43 swivelly positioned interiorly of pivot bracket 36 on a vertical swivel axis laterally displaced from the rotational axis of rotatable vertical driven fork 54. Said rotatable vertical driven fork 54 transmitting torque to vertical drive shaft 53 integral therewith. The matching multiple splines of the lower end of rotatable vertical drive shaft 53 transmitting torque to rotatable bevel pinion and shaft 58 to bevel gear 65 meshing therewith. Said bevel gear 65 rotatable with horizontal propeller shaft 62 transmits torque to propeller 69 thereon for propelling the boat.

The spacer 47 positioned between tubular housing 48 and tiller bar 46 being removed or replaced with a similar spacer 47 of greater or lesser vertical thickness positions said tubular housing 48 a greater or lesser distance below the bottom 12 of a boat. The matching multiple splines of vertical drive shaft 53 and bevel pinion and shaft 58 permitting vertically telescoping power transmitting connection therebetween.

The vertical divergent tube 75 rotatable with vertical drive shaft and fork 53, 54 journaled interiorly of cavity- 55 of tubular housing 48 raising lubricating oil from the lower end thereof to the upper end thereof by centrifugal action whereby the ball bearing and oil seal 57, wherein said drive shaft and fork 53, 54 is journaled, is lubricated and cooled. The vertical passage 78 of tubular housing 48 permitting further oil recirculation from the horizontal bore 61 of the lower end of tubular housing 48 to cavity thereof by centrifugal action of said lubricating oil between the outer surface of said divergent tube and the Wall of cavity 55.

The thrust of propeller 69, during forward propulsion of a boat, on tubular housing 48 depending from pivot bracket 36 being transmitted by cable 87 therefrom to cable terminations 94. Said cable terminations 94 bearing against adjustable tubular stops 93 depending on stop brackets 91 secured to the transom 11 of a boat, whereby the substantially vertical position of tubular housing 48 may be adjusted by positioning adjustable tubular stops 93. Upon pivotal movement of pivot bracket 36 said flexible cable 87 moves forward through tubular stop 93, being prevented from lifting radially off sheave segments 86 of pivot bracket 36 by multiple horizontal rods 113 engaging flanges 112 of side covers 110. Aforementioned cable terminations 94 being secured to a tension member 95 operably connected to remote control means whereby pivot bracket 36 and tubular housing 48 depending therefrom may be pivotally raised, by said remote control means, above the bottom 12 of a boat.

The thrust of propeller 69, during reverse propulsion of a boat, on tubular housing 48 depending from pivot bracket 36 being transmitted by shear pin 109 of said pivot bracket 36 to engaging reverse lock lever pivotally secured to mounting bracket 18. Said reverse lock lever 105 being restrained from pivotally disengaging said shear pin 109 by interference of control lever 28 of marine transmission 21 and conforming arcuate portion of reverse lock lever 105. Shear pin 109 beingof a size to avoid mechanical damage to pivot bracket 36 and dependent parts upon forward moving collision of tubular housing 48 with objects in the water.

Reverse lock lever 105 being held in engagement with shear pin 109 of pivot bracket 36 by tension spring 104 during forward movement of the boat whereby water drag on vertical tubular housing 48 and propeller 69 tlgereon will not cause pivotal movement of pivot bracket 3 The vertical tubular housing 48 with propeller 69 at the lower end thereof being swivelly positioned for guidnected by horizontal rods 1 13.

ing movement of the boat. Said vertical tubular housing 48 and tiller bar 46 being dependent from swivel disk 43 swivelly positioned within pivot bracket 36, the swivel axis thereof being laterally displaced from the thrust line of said propeller 69. Whereby the torque of vertical drive shaft and fork 53, 54 on the vertical tubular housing 48 during forward propulsion of a boat is balanced by the torque produced by propeller 6-9 thrust and said lateral displacement of said swivel axis from the propeller 69 thrust line. The swivel angle of swivel disk 43, tiller bar 46 and vertical tubular housing 48, with propeller 69 positioned at the lower end thereof, being determined by tiller cables 99 secured to the ends of tiller bar 46. Said tiller cables 99 being positioned by remote control means (not shown) as required in guiding movement of a boat.

The mounting bracket 18 and marine transmission 21 dependent therefrom being adjustably adaptable to transoms having various construction angles in the horizontal and vertical planes. Said mounting bracket 18 being positioned by spherical prominence 17 thereof positioned in a spherical opening of transom frame 14 secured to transom 11 of a boat, and clampingly positioned by longitudinally adjustable mounting nuts 24 of marine transmission 21 hearing against depressions 25 of said transom frame 14.

The universal joint formed by drive fork 30, link blocks 80, links 8 3 and driven fork 54 with pivotal connecting parts and the pivot bracket 36 being covered on the upper and rear sides thereof by side covers 110 and a multiplicity of hinged accordian panels 114 intercon- It may readily be seen as pivotal motion of said pivot bracket 36 from vertical downward position to vertically upward position occurs said multiple accordian panels 114 fold outwardly in accordian fashion without restraint of said pivotal motion by said pivot bracket 36. It may further readily be seen that tension spring 117 securing the last accordian panel 114 to pivot bracket 36 causes said multiple accordian panel 114 to unfold in accordian fashion as said pivot bracket 36 returns to a vertical downward position.

From the foregoing, the construction and operation of the device will be readily understood and further explanation is believed to be unnecessary. However since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the invention to the exact construction shown and described, and accordingly, all suitable modifications and equivalents may be resorted to, falling within the scope of the appended claims.

What I claim as my invention is:

1. A drive unit for boats having an inboard engine, having a rotatable substantially horizontal drive shaft operably connected to said engine and journaled within a mounting bracket depending from the boat whereby an end of said rotatable substantially horizontal drive shaft is positioned outboard of said boat, pivotally depending from said mounting bracket on a substantially horizontal pivotal axis is an outboard pivotal pivot bracket, and swivelly depending from said pivotal pivot bracket is a swivelable vertical tubular housing having a substantially vertical swivel axis which is laterally displaced from the axisof a vertical drive shaft journaled therein which is operably connected to the aforementioned substantially horizontal drive shaft.

2. A drive unit for boats having an inboard engine, having a rotatable substantially horizontal drive shaft operably connected to said engine and journaled within a mounting bracket depending from the boat whereby an end of said rotatable substantially horizontal drive shaft is positioned outboard of said boat, pivotally depending from said mounting bracket on a substantially horizontal pivotal axis is an outboard pivotal pivot bracket, and swivelly depending from said pivotal pivot bracket UNITED of aforementioned pivotal pivot bracket.

1 References Cited by the Examiner STATES PATENTS Shaxw 646 Griffith 115- 35 Fitzgerald 115-'35 Crosby 11541 Bossen.

2/1947 Law 11541 12/ 1950 Wanzer 11535 7/1956 Hills 11541 10/1961 Hansson 115 35 2/ 1963 Shipley 115-41 FOREIGN PATENTS 5/ 1960 France 1/ 1931 Great Britain.

MILTON BUCH'LER, Primary Examiner.

EMILE PAUL, FERGUS S. MIDDLETON, Examiners.

P. J. WALSH, R. G. BESHA, A. H. FARRELL,

Assistant Examiners. 

1. A DRIVE UNIT FOR BOATS HAVING AN INBOARD ENGINE, HAVING A ROTATABLE SUBSTANTIALLY HORIZONTAL DRIVE SHAFT OPERABLY CONNECTED TO SAID ENGINE AND JORNALED WITHIN A MOUNTING BRACKET DEPENDING FROM THE BOAT WHEREBY AN END OF SAID ROTATABLE SUBSTANTIALLY HORIZONTAL DRIVE SHAFT IS POSITIONED OUTBOARD OF SAID BOAT, PIVOTALLY DEPENDING FROM SAID MOUNTIONG BRACKET ON A SUBSTANTIALLY HORIZONTAL PIVOTAL AXIS IS AN OUTBOARD PIVOTAL PIVOT BRACKET, AND SWIVELLY DEPENDING FROM SAID PIVOTAL PIVOT BRACKET IS A SWIVELABLE VERTICAL TUBULAR HOUSING HAVING A SUBSTANTIALLY VERTICAL SWIVEL AXIS WHICH IS LATERALLY DIS- 